Electric soldering-iron.



l. T. GRIFFIN.

ELECTRIC SOLDERNG IRON.

APPLICATION mu: v.3. 19l6.

Patented D60. 18, 1917 2 suns-sun 1.

Jirmas J. T; GRIFFIN.

' ELECTRIC SOLDERING IRON.

APPLICATION mm mmi 1915., 1,250,856. Patented Dec. 18, 1917.

2 SHEETS-SHEET Z- UNITED STATES PATENT OFFICE.

I'm-ES T. GRIFFIN, OF OAK PARK, ILLINOIS, ASSIGNOR TO WESTERN ELECTRIC COM- Pm, INCORPORATED, OF NEW YORK, N, Y., A CORPORATION OF NEW YORK.

ELECTRIC SOLDEBING-IEON.

Specification a! Letter: remit.

Patented Dec. 18, 1917.

pllcation filed January 8, 191a. Serial m. 10,001,

To all whom it may concern:

Be it known that I, JAMES T. Gum, a citizen of the United States, residing at Oak Park, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Electric Soldering- Irons, of which the following is a full, clear, concise, and exact description.

This invention relates to improvements in electric soldering irons.

The object of the invention is to provide a soldering iron-made up' of readily separable parts, one of which parts is 'aheating unit hclicqs.

ablyifoubled back on themselves and twist of mexpensive construction, whereby the heatin unit may be removed from time to time burned out, or a unit ofdifferent wattagemay be substi uted for the one in use .with a minimum 0 delay and expense.

he soldering iron illustrated in the accompanying drawings will serve to.disclose one embodiment of the invention; Figure 1 is an elevation thereof partly in section. Fig. 2 is an enlarged elevation, partly in section, ofthe heating unit. Fig. 3 is a section on the line 3-3 of Fig. 2. Fig. 4 is an elevation, partly in section, of certain parts of the soldering iron detached from each other. Fig. 5 is an enlarged sectional elevation of one of the inclosed pprts, Fig. 6 ban and elevation thereof. i i5 7 is a section on the line 7-7 of F i 5. ig. 8 is a rspective view of the insulating core.

he heating unit for the soldering iron is provided with a core 1 of any suitable refractory insulating material, various mixtures of cement being well adapted for this purpose. Said core has acentral opening 2 therethrough and a notch 3 in one end. The resistor consists of any suitable material, preferably in the form of a wire 4, which is wound into a helix with a straight length on each end, and the helix thus formed is then wound around the core 1, as shown in Fig. 2, to form a large helix. The individual tur sof the small helix are out of contact wit each other and the turns of the large helix are similarly spaced apart to prevent contact. One of the straight lengths of the resistance wire is passed through the notch 3 and then through the opening 2, whereby it is maintained out of contact with the Both ends of the wire are prefered t form terminal conductors 5 and 6 of grea r size, strength and conductivity than the intermediate portion of the wire constituting the helices. The ends of the core are wrapped with asbestos strips 7, 8 to hold the resistor in place temporarily. In order to permanently hold the turns of the helices in fixed spaced relation and to properly protect them, they are embedded in cement. .This is done by introducing cement into a mold in which the core, havin the resistance wire wound thereon, is p seed. The finished product has the appearance ofa cylinder 9, made of refractory insulating material, from which the terminal conductors 5 and 6 protrude, the original core '1 being completely inclosed. The heating unit thus formed is cfiicient, durable and of inexpensive construction.

other end. of the tube 16. It is provided with a split sleeve 18, projecting from the end thereof, and clamped down upon said tube 16 by a nut 19.

A washer 20 of asbestos or other suitable insulating material is located Within the shell 10 between the heating unit and the head 14 (Fig. 4), and has a. pair of openings 21 therein. The terminal conductors 5 and 6 pass through said openings and through a pair of slincd openings 22 in an insulating cylinder 23 located withinthe tube 16. Contact between said conductors is thus prevented.

Beyond the cylinder 23, a spool of insulat ing material 24 is located. This spool, as shown in Fig. 5, has a rpduced middle portion 25, having a pair of grooves in its oppo' site faces within each of which fits a sheet metal channel 26. These channels communicate \vitirn pair of openings 27, passing through one end of the spool and with a second pair of openings 28 passing through the other end thereof, which lead to a recess 29, the latter being adapted to receive the end of the usual flexible cord 30 containing two conductors 31, 32. Said conductors pass through the openings 28 and meet the terminal conductors 5 and 6 which pass through theopenings 2.7. The ends of'the respective conductors are soldered to the sheet metal channels 26, and may be soldered to each other, the joints being thereafter wrapped with asbestos string 33, as shown. .in F-ig. 1. The. lower end of the tube 16"is' provided with a pair of opposit'ely disposed openings 34", arranged 'just over the points where the conductors are.

soldered together. "Ihese openings facilitate-the unsoldering of the wires when it is de'sired'to renew the heating unit, as the ti ofa soldering iron can be introduce through said openings. The spool 24 and the cord are arranged-to slip loosely within the tube 16, whereby said spool and associated parts may be drawn out of the upper, end of said tube to facilitate the soldering or unsoldering of the wires, when the screw'-35, which holds said. s 001 11.

place'within said tubing, is remove Said openings are used only in case it is diflicult to withdrawisaid parts, in which case the unsolderin may be efi'ected without said withdrawa N 'With the construction described, it will be seen that by simply removing'a set screw the casing'lOmay be unscrewed and removed, ancl the heating unit rendered accessible by pulling the terminal'conductors and other associated partsout of the end of said tube. The wires may then be'quic'kly .unsoldered and the new unit substituted.

littlece'ment may be used when the unit is being inserted in its case, to fill any slight clearance space that may exist, thereby reducing the heat potential drop. The .ex-

pense of the'original unit is'so sli ht that if it b urns'out it is simply discar ed and a new one substituted. The substitution inay also be effected where it is desired to change the soldering iron to one havin a difierent wattage for a d-ifierent class o work. 7

The soldering iron may also be-used as a branding iron, by substituting for the tip 12' a suitable heat conducting extension carrying the raised letters or figures which it is desired to imprint on the object to be branded. One important illustration of such-use is that whcrein the characters are branded on the hard rubber ends of 'the spools on which coils are wound, in telephone practice. Various other uses are contemplated. Hence the invention is not limited to a structure intended primarily for soldering, but should includeall such as are'fadaptedto apply heat more or. less locally where the heat is generated by an electrical heating unit readily replaceable withinits heat conducting container.

\Vhat is claimed is:

1. A soldering iron, comprising a length ofntubing,;a S oor therin hatifig elongated grooves,-openings in said spool at'the ends of said grooves, a detachable casing at 'one end of said tubing,,a heatingunit remo'vahly mounted therein, conductors extending from said heating unit through one end of said spool into-said grooves, and external conductors assing through openings in the other en of said spool into said grodi'es and joined to said first conductors.

2L soldering iron, comprisinga heat conducting casing, a heating unit. removably mounted therein, ,tubing extendin from said casing, a handle thereon, a spoo within.

said tubing, an insulatin cylinder within said tubing, said'spool an cylinder having ali ned openings, conductors extending .from said heating unitthroughsaid openin ex-'.

ternal conductors passing throughsai han-.

dle and through further opemngsin said spool and soldered to said first conductors, said tubing having a pair of openings-arranged o'vei' said soldered connection to pro vide access thereto when the handle is removed, and means for clamping said handle in place. I i,

3. In anelectric soldering iron,,'a

theintermediate portion of said spool, and metal channels fitting said grooves.

- 0010f insulating. material having a,pa1r o open ings in opposite ends, a pair of. grooves in 4. A soldering j iron comprising a heat i conducting casing,' 'a heating unit removably mounted therein, aplug mounted in one end:

a tip positioned therein, said heating unit. VI

of said heat conducting casing and havin comprising a substantially centrallyaper;

tured core haying a notch therein,

lix .of

resistance wire wound thereon,- one end of,

which is' ada pted to be caught by said.notchand to extei 'd throughthe aperturein'said core to form 'a terminal, the otherrend of, said wire extending from the outer circumferenceof said ,co'readja'centthe first inentioned end thereof to form a second. terminal, means wound aroundoppositeendsof, saidcore to secure said resistor in place, and I a covering of molded plastic insulation .com-..

lete'ly covering said elements and contact-ii lls ing'with said eat conducting ,ca'singl and said plug to conduct heat to said tip.

5. In an electric solderingirom'ahandle,

a heat conductingfcasing', a plugprovided with a tip positioned in one endof saidca's- 'ing and a heating unit mounted within-said casing and contacting with the wall'sjt'hereof and :with said plug to cond uct heat"to said tip, said heating unit comprising a; centrally 'apertured "core having a notch "therein, av

helix of resistance wire wound thereonin helical form, one, end of saiduwire being adaptedto be caught by said notch and to extend through said aperture, means-wound around opposite ends of said cor'et secure said resistor in place, and a covering ofiao molded plastic insnln Lion completely covergrooves and joined to said first conductors, ing said wire and said core and extending and openings in said tube arranged over through said'aperture. said grooves to provide easy access to the 6. A soldering iron, comprising a length joined ends of said conductors when said 5 of tubing, a handle thereon, a spool therein handle is removed.

having elongated grooves, a casing at one In witness whereof, Ihereunto subscribe end of said tubing, a. heating unit mounted my name this 29th day of December, A. D. therein, conductors extending from .said 1915.

heating unit into the grooves in said spool,

, 10 external condnctors extending into said JAMES T. GRIFFIN; 

